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KScope 11 - In the rearview mirror

Last Saturday afternoon I arrived back home and after two nights of (more or less) sleep, this morning I headed for the airport again to fly to Stockholm for my current project. So while sitting in my hotel room, I (finally) have some time to blog about last weeks Kscope11....As always, this Kscope was packed with great sessions too. After Sundays symposium, complete filled by the APEX Development Team - at least for the track I was most interested in - Monday started off with "Web services for the REST of us" by Jason Straub. Jason showed how easy it is in APEX to consume (for instance) Yahoo web services and how to use APEX as a front end for Amazon's cloud storage. If you ever have trouble getting the XPath expression right, you might consider usingAltova XMLSpy. This tool (not free though!) can be used for determining the the XMLPath expression, just by clicking on the node you're interested in. And when debugging web services can be quite cumbersome, take a look at ProxyTrace. This can be used for debugging the web service calls, as all calls go through this "proxy" and are logged.
Next Patrick Wolf did a session on the Improved Error Handling in APEX 4.1. "Improved" is a sort of understatement, as in the current version Error Handling is lacking - and that's why a lot of people created their own framework to handle errors (and so did I). But when 4.1 is available, we can get rid of all this code and use the built in features, that are very nice. You can define a error handling function on application level and override that on page level (if you find the need). To me, this is one the most important improvement of 4.1."APEX Page Stitching" was next on my schedule. It was all about using Ajax calls to retrieve snippets from pages and embed these in another page in order to create a master-detail-detail report. The presentation was not as smooth as the presenter would have liked it (I guess) and IMHO you just should convince your users that what made sense in an Oracle Forms environment, doesn't necessarily makes sense in a web environment (never seen such a report on Facebook or Amazon). "APEX Tight Tabular Forms" was the last one of this Monday. Very much covered all the nasty details you need to know (but do not want to know) when working with tabular forms. My advice: Don't use them if you can - and when you have to : stick to the wizard!
That night the guys from Redgate invited us to a very nice dinner at the Parkers' Lighthouse. Thanks again, lads!

Tuesday's first session was "Plug-ins - beyond the basics" by Dan McGhan. It was one of the (many?) sessions about Plug-ins at Kscope. But luckily Dan had the first one, so he could explain this still rather complicated stuff very thorough. Then there was the "vendor slot". I went to see "FormSpider, PL/SQL meets Web 2.0". They claim that all their applications is 100% PL/SQL, but the first screen with code that we saw was...XML. But that was "only" needed for the UI.... But apart from that, you seem to need an awful lot of code to accomplish some simple task as moving to a set of records. They also claim that they can convert Oracle Forms to this tool. So not only the UI, which is rather easy, but also the Form triggers. The examples shown where not very convincing, as they contained 1. a goto and 2. an assignment. I would like to have seen more - complicated, real world - examples. The application is skinnable (adapting the colors etc to your own likings), but - as expected - you need to add some CSS for that. And you need to write Javascript to incorporate third party libraries (like jQuery). So that was it for 100% PL/SQL... The main driver the vendor always uses for this tool, is the lack of internet broadband in Ethiopia. This tools uses the minimum of bandwidth possible - as they only post and get the changes instead of the whole HTML document. But that is hardly an issue in the more developed countries where broadband internet is everywhere! You can check out their site : http://theformspider.com/
You can also register for a hosted instance version there to try it out yourself.
Then the award-winning, best session of the conference : "APEX4 + HTML5 = Awesome!" by Martin d'Souza. Not only the way Martin presented it was awesome, but also the content made you want to try this stuff immediately! Geolocation and push messages from the server were my favs! If you to know more on this subject : http://diveintohtml5.org/
My last session of this day was my co-presentation with Marco about the "XFILES": a neat way to implement versioning for APEX using APEX and the XML-DB Repository. So a 100% database centric approach, that runs even on XE! The presentation went pretty well and we got positive feedback. Even from the attendees of the APEX Dev Team, so you never know if this (or something like this) will make it into a future release.... If you want it now, download the application for Sourceforge : http://sourceforge.net/projects/xace/.
The ACE Dinner, as always very well organized by Vikki, Lillian and Justin, was the last "session" of this day.

The first session on Wednesday was "All about Location: APEX, Spatial and Maps". Another great session on a topic I am not very familiar with. I should dive into this geo-stuff when I've got the chance. Some of the functionality is even available without an additional license! And you can do so much with it, like determining your clients within a 50 mile radius from your current position (HTML5!).
The next session I attended was not very well picked (understatement). When the presenter asked: "Can you read this from the back", we said "No!" - and then he said "Ok, then I can just proceed". Huh??? No further comments - or naming...
Next I did my second presentation about "Software Architecture for APEX". This was my first presentation using my iPad, with my iPod Touch as a remote. Technically spoken this just went perfect! I'll do that again! And although in my opinion the content needs some polishing, I got positive reviews. So it can only get better next time!
Then Dan did a presentation on "Manual Tabular Forms". Again the message was: don't. Because it is a pain . After that, the fastest speaking presenter in this area, Raj Mattamal, jumped back and forth and up and down on Ajax processes. The presentation was typically Raj: energetic, but a little bit chaotic as well... The last session - before we all headed up to the Queen Mary - was Doug's "Sparkline Plug-in". A tiny, nifty chart that renders as a page item (Wikipedia). It should be available "soon"...
And then there was the party... And what a party it was! Of all 4 Kscope's I attended, this was the best party ever! By far! It included free food and drinks, a duelling piano bar, a poker/blackjack room, a comedian, a great band playing rock music on request on the upper deck and fire works to finish it off! And the location was the Queen Mary, a Titanic-like cruise ship across from Long Beach. How awesome!

And Thursday morning was not so easy of course. A lot of sleepy eyes and small headaches... But Martin did another great session on "How to be creative II". His message was: for every problem, there is a solution. Most of the time. He had some nice examples to keep the crowd awake. You should check out his console wrapper! This Kscope's last session (for me) was "UI Design" by Shakeeb. Apart from a cool Prezi presentation - the first one I've seen here - the content was great too. He demo'ed how to make your APEX application look exactly like Apples website. His tips (just follow the links or Google for more info): HTML5 (again), Modernizr.com (to create browser and device independent webistes), Compass (to create browser indenpendent CSS files) and use CSS sprites instead of multiple images. Great session - I learned a lot!

And that was the end of another great Kscope. Looking forward to the 2012 version in San Antonio, Texas - it will be smoking hot out there. You can register now and already submit abstracts (kscope12.com)!
See you all there....

Until we had the IG, we showed the data in a report (Interactive or Classic). Changes to the data where made by popping up a form page, making changes, saving and refreshing the report upon closing the dialog. Or by clicking an icon / button / link in your report that makes some changes to the data (like changing a status) and ... refresh the report.
That all works fine, but the downsides are: The whole dataset is returned from the server to the client - again and again. And if your pagination size is large, that does lead to more and more network traffic, more interpretation by the browser and more waiting time for the end user.The "current record" might be out of focus after the refresh, especially by larger pagination sizes, as the first rows will be shown. Or (even worse) while you…

Nowadays Docker is everywhere. It is one of the main components of Continuous Integration / Continuous Development environments. That alone indicates Docker has to be seen more as a Software Delivery Platform than as a replacement of a virtual machine.

However ...

If you are running an Oracle database using Docker on your local machine to develop some APEX application, you will probably not move that container is a whole to test and production environments. Because in that case you would not only deliver a new APEX application to the production environment - which is a good thing - but also overwrite the data in production with the data from your development environment. And that won't make your users very excited.
So in this set up you will be using Docker as a replacement of a Virtual Machine and not as a Delivery Platform.
And that's exactly the way Martin is using it as he described in this recent blog post. It is an ideal way to get up and running with an Oracle database …

If you created your own "updatable reports" or your custom version of tabular forms in Oracle Application Express, you'll end up with a query that looks similar to this one:
then you disable the "Escape special characters" property and the result is an updatable multirecord form.
That was easy, right? But now we need to process the changes in the Ename column when the form is submitted, but only if the checkbox is checked. All the columns are submitted as separated arrays, named apex_application.g_f0x - where the "x" is the value of the "p_idx" parameter you specified in the apex_item calls. So we have apex_application.g_f01, g_f02 and g_f03.
But then you discover APEX has the oddity that the "checkbox" array only contains values for the checked rows. Thus if you just check "Jones", the length of g_f02 is 1 and it contains only the empno of Jones - while the other two arrays will contain all (14) rows.
So for processing y…